A multi-physical field in-situ detection system for semiconductor processing

Abstract

The application relates to the technical field of semiconductor equipment detection and debugging, and discloses a multi-physical-field in-situ detection system for semiconductor processing, which comprises a wafer and a computer terminal; a main control circuit, a sensor set, a wireless signal transmission circuit, a charging and discharging circuit and a storage circuit are loaded on the wafer; the main control circuit is connected with the sensor set, the wireless signal transmission circuit, the charging and discharging circuit and the storage circuit; the charging and discharging circuit is used for realizing offline power supply; the computer terminal is in wireless communication with the main control circuit; during work, the sensor set is used for collecting various physical quantities of a semiconductor chamber; the main control circuit stores the collected various physical quantities into the storage circuit and transmits the collected various physical quantities to the computer terminal in a wireless or wired mode; the computer terminal generates a cloud picture of a scalar field and a curve picture of physical quantity changes with space and time according to detection information of each physical quantity, so as to assist in process parameter debugging of the semiconductor equipment.

Description

Technical Field

[0001] This invention relates to the field of semiconductor equipment technology, and in particular to a multiphysics in-situ detection system for semiconductor manufacturing processes. Background Technology

[0002] To improve the debugging accuracy of semiconductor equipment processes, it is necessary to test the physical field within the semiconductor equipment cavity using sensors. In existing technologies, testing the physical field within the semiconductor equipment cavity requires opening the cavity cover and then inserting a wired sensor for detection. This presents several problems: 1) Opening the cavity in most semiconductor equipment is cumbersome; 2) Due to the presence of wires, the cavity door or cover cannot be completely closed, affecting the vacuum level and gas flow field, and failing to fully simulate the actual conditions in production; 3) Some semiconductor cavities are less than 10mm high, which limits the sensor height; 4) In most cases, high-frequency measurements and multiple numerical calculations (average, median, maximum, minimum, and sigma values ​​for each region) are required across multiple areas of the entire wafer, making conventional sensor operations cumbersome. Summary of the Invention

[0003] In view of the problems existing in the prior art, the purpose of the present invention is to provide a detection system and method for easily detecting various physical quantities in a semiconductor cavity, and to provide at least a beneficial option or create conditions for solving one or more technical problems existing in the prior art.

[0004] To achieve the above objectives, the present invention adopts the following technical solution.

[0005] A multiphysics in-situ detection system for semiconductor manufacturing processes includes a carrier wafer and a computer terminal. A main control circuit, a sensor array, a wireless signal transmission circuit, a charging / discharging circuit, and a storage circuit are mounted on the carrier wafer. The main control circuit is connected to the sensor array, the wireless signal transmission circuit, the charging / discharging circuit, and the storage circuit. The charging / discharging circuit is used to provide offline power. The computer terminal communicates wirelessly with the main control circuit.

[0006] During operation, the sensor set is used to collect various physical quantities of the semiconductor cavity. The main control circuit stores the collected physical quantities in the storage circuit and transmits them to the computer terminal wirelessly or via wired means. The computer terminal generates a three-dimensional distribution map of the physical quantities and a curve of the physical quantities changing with space and time based on the detection information of each physical quantity using a finite element algorithm, which is used to assist in the debugging of process parameters of semiconductor equipment.

[0007] More preferably, the sensor set acquires data in three ways: real-time acquisition, delayed acquisition, and scalar acquisition. Real-time acquired data is transmitted back to the computer terminal wirelessly. Delayed and scalar acquired data are stored in a storage circuit. After the process is completed, the wafer is sent out again, and the data is then read back to the computer terminal. Delayed acquisition refers to acquisition starting after a set time has elapsed. Scalar acquisition refers to acquisition starting after a set parameter has been reached.

[0008] More preferably, a wireless charging coil is also mounted on the wafer, and the wireless charging coil is connected to the charging and discharging circuit to realize wireless charging.

[0009] More preferably, the wireless charging coil and the charging / discharging circuit are located at the exact center of the wafer.

[0010] More preferably, the physical quantities include one or more of the following: temperature, humidity, plasma concentration, air pressure, distance, orientation, particle size, illuminance, and shear force.

[0011] A continuous temperature-time-space distribution map of the wafer within the cavity is obtained by measuring the temperature.

[0012] A continuous distribution map of humidity in time and space within the wafer cavity is obtained by measuring humidity.

[0013] By measuring the gas pressure, a continuous distribution map of vacuum or pressure-time-space within the cavity of the wafer can be obtained.

[0014] The distance distribution map between the wafer and the cavity cover is obtained by measuring the distance, which is used to adjust the distance and parallelism between the cover and the wafer.

[0015] By measuring the attitude, the wafer's velocity, displacement, acceleration, tilt angle, and vibration during the movement process are obtained, thus determining the state of wafer transfer during the wafer transfer process. Through multi-state combined analysis, it can be determined whether there is looseness or other abnormalities in the wafer transfer equipment. On equipment with a rotating structure, the concentricity between the wafer and the rotating structure is obtained by analyzing the attitude data.

[0016] The environmental particle size of the wafer during its movement is obtained by measuring the particle size.

[0017] The intensity of different types and wavelengths of light on the wafer surface is obtained by measuring illuminance.

[0018] The forces applied to the wafer, parallel to and perpendicular to the wafer surface, are obtained by measuring the shear force.

[0019] The distribution of plasma within the chamber is detected by measuring the plasma concentration.

[0020] More preferably, after the sensor assembly is mounted on the wafer, it undergoes two calibrations and multiple verifications. The first calibration is to calibrate the acquisition accuracy of the circuit by using a standard load. The second calibration is performed using dedicated calibration equipment for each of the measured quantities. When calibrating with the dedicated calibration equipment, multiple calibrations and verifications are performed using cross-validation of data from multiple sources.

[0021] More preferably, the battery and the main control circuit are both mounted in a high-temperature insulation structure, and the sensor set is connected to the main control circuit in the high-temperature insulation structure through a wafer surface circuit; the wafer surface circuit is attached to the surface of the wafer by a process of metal sintering after trenching, metal screen printing, metal deposition, or metal deposition after etching.

[0022] More preferably, the high-temperature insulation structure includes a loading box, which is suspended on the wafer by a metal sheet and a support foot. The loading box has a heat insulation layer and a phase change layer on the side near the wafer. A ceramic gasket is provided in the loading cavity of the loading box, and the battery and / or the main control circuit is mounted on the ceramic gasket.

[0023] More preferably, the phase change material of the phase change layer is a bismuth alloy material with a melting point of 80-120℃, and the heat insulation material of the heat insulation layer is a ceramic material.

[0024] More preferably, the wafer is bonded together with upper and lower silicon wafers, with corresponding grooves on the upper and lower silicon wafers, and the grooves cooperate to form a sensor mounting cavity; an insulating film is provided between the upper and lower silicon wafers to isolate the electric field; the upper and lower silicon wafers are bonded together with an adhesive, and the bonding surfaces of the upper and lower silicon wafers are not in the same plane as the sensor circuit board; the upper and lower silicon wafers are phosphorus-doped silicon wafers, and the insulating film contains polyimide radio frequency shielding coating.

[0025] Compared with the prior art, the present invention has at least the following beneficial effects.

[0026] I. This invention, by mounting sensing devices such as temperature sensors, humidity sensors, pressure sensors, illuminance sensors, and particle size sensors on a wafer, and combining them with wireless communication and wireless charging, enables the detection of various physical quantities in the semiconductor equipment process chamber during semiconductor manufacturing. This facilitates the generation of three-dimensional distribution maps and curves showing the changes of physical quantities with space and time through finite element algorithms, effectively reducing the difficulty of process debugging for semiconductor equipment and making process debugging simpler and more accurate.

[0027] Second, by setting up high-temperature insulation and electric field shielding structures, the high-temperature resistance and anti-interference problems when integrating various types of sensors onto the same wafer to form a carrier wafer are effectively solved.

[0028] Some other beneficial effects of the present invention will become more apparent in the following description or may be learned by practice. Attached Figure Description

[0029] Figure 1 The diagram shown is a structural schematic of the multiphysics in-situ detection system of the present invention.

[0030] Figure 2 The diagram shown is a structural block diagram of the multiphysics in-situ detection system of the present invention.

[0031] Figure 3 The diagram shown is a schematic of the installation of a high-temperature insulation structure.

[0032] Figure 4 The diagram shows the connection between the loading box and the wafer.

[0033] Figure 5 The diagram shown is a schematic of the internal structure of the loading box.

[0034] Figure 6 The diagram shown is a schematic of the anti-interference installation structure.

[0035] Explanation of the reference numerals in the attached figures.

[0036] 1: Wafer, 2: Main control circuit, 3: Sensor assembly, 4: Wireless charging coil, 5: Wireless signal transmission circuit, 6: Battery, 7: Charging and discharging circuit, 8: Charging port, 9: Storage circuit, 10: Wafer surface circuit, 11: Loading box, 12: Metal sheet, 13: Support foot, 14: Heat insulation layer, 15: Phase change layer, 16: Ceramic pad, 17: Sensor mounting cavity, 18: Insulating film. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0038] Reference Figure 1 , Figure 2 As shown, a multiphysics in-situ detection system for semiconductor manufacturing processes includes a wafer 1 and a computer terminal. The wafer 1 is equipped with a main control circuit 2, a sensor array 3, a wireless signal transmission circuit 5, a battery 6, a charging / discharging circuit 7, a charging port 8, and a storage circuit 9. The main control circuit 2 is connected to the sensor array 3, the wireless signal transmission circuit 5, the charging / discharging circuit 7, and the storage circuit 9. The charging / discharging circuit 7 is connected to the battery 6 and the charging port 8. The computer terminal communicates wirelessly with the main control circuit 2.

[0039] During operation, the sensor set 3 is used to collect various physical quantities in the semiconductor cavity. The main control circuit 2 stores the collected physical quantities in the storage circuit 9 and transmits them to the computer terminal wirelessly or via wired means. The computer terminal generates a three-dimensional distribution map of the physical quantities and a curve of the physical quantities changing with space and time based on the detection information of each physical quantity, thereby reducing the difficulty of process debugging of semiconductor equipment.

[0040] In this embodiment, the sensor set 3 acquires data through real-time acquisition, delayed acquisition, and scalar acquisition. Real-time acquired data is immediately transmitted wirelessly back to the computer terminal. Delayed and scalar acquired data are stored in the storage circuit 9. After the process is completed, the wafer is sent out again, and the data is read again. Delayed acquisition refers to acquisition starting after a set time has elapsed. Scalar acquisition refers to acquisition occurring after a set parameter has been reached, such as reaching a set temperature. Preferably, the data in the storage circuit 9 can be continuously stored for more than 30 minutes, while the main process stages are generally within 20 minutes, meeting the storage requirements.

[0041] The physical quantities include: temperature, humidity, plasma concentration, air pressure, distance, orientation, particle size, illuminance, and shear force, etc. Obviously, the specific physical quantities can be selected and set by those skilled in the art according to different actual needs. By changing the types of sensor sets, the detection of different physical quantities can be achieved.

[0042] It should be noted that wafers with different types of sensors undergo two calibrations and multiple verifications. The first calibration calibrates the acquisition accuracy of the circuit using a standard load. The second calibration uses dedicated calibration equipment for each measured quantity; for example, temperature is calibrated using a constant-temperature oil bath, and humidity is calibrated using a constant-humidity chamber. During professional calibration, multiple calibrations and verifications are performed using cross-validation of data from various sources (instruments in the professional calibration chamber, authoritative testing instruments in the field of physical quantity measurement, and measuring tools used by the testing organization). Finally, the carrier wafer is calibrated to ensure the detection accuracy after the sensor is mounted on the wafer.

[0043] In this embodiment, a wireless charging coil 4 is preferably also mounted on the wafer 1. The wireless charging coil 4 is connected to the charging and discharging circuit 7 to realize wireless charging and better achieve wireless detection operation. In some embodiments, the wireless charging coil 4 may be omitted, and is not limited to this embodiment.

[0044] Preferably, the wireless charging coil 4 and the charging / discharging circuit 7 are located at the exact center of the wafer 1, so that no matter how the wafer 1 rotates, the wafer can be charged as long as the center of the wafer and the center of the charging carrier are aligned.

[0045] In this embodiment, battery 6 is preferably a solid-state or semi-solid-state battery to meet the application requirements in vacuum or heated environments. The capacity of battery 6 will vary depending on the thickness of the wafer, but it must maintain a minimum of 2 hours of battery life to meet the process requirements of most semiconductor devices.

[0046] In this embodiment, the temperature is measured by a temperature sensor, and a continuous temperature-time-space distribution map of the wafer inside the cavity is obtained by measuring the temperature.

[0047] Humidity is measured by a humidity sensor, and the humidity measurement yields a continuous time-space distribution map of the wafer within the cavity.

[0048] The air pressure is measured using a vacuum or pressure sensor. By measuring the air pressure, a continuous distribution map of the vacuum or pressure in time and space of the wafer inside the cavity is obtained.

[0049] Distance is measured using a capacitive distance sensor. By measuring the distance, a distance distribution map of multiple points on the wafer relative to the cavity cover is obtained, which is used to adjust the distance and parallelism between the cover and the wafer. For cavities containing plasma and radio frequency components, the relationship between the distance and parallelism between the cavity cover and the wafer can affect the manufacturing process.

[0050] Attitude is measured using accelerometers. These accelerometers can measure the wafer's velocity, displacement, acceleration, tilt angle, and vibration along three axes (X, Y, and Z) during movement. This allows for the detection of the wafer's transfer status during the transfer process. By combining and analyzing multiple states, it is possible to determine if the transfer equipment is loose or has other abnormalities. On equipment with rotating structures, analyzing the attitude data can also determine the concentricity between the wafer and the rotating structure.

[0051] Particle size is measured using particle size sensors or laser sources and photosensitive devices to obtain the environmental particle size of the wafer during its movement.

[0052] Illuminance is measured using illuminance sensors, UV sensors, or thermopile sensors, which can obtain the intensity of different types and wavelengths of light on the wafer surface.

[0053] Shear force is measured using strain gauges or piezoelectric shear force sensors to detect forces applied to the wafer that are parallel to and perpendicular to the wafer surface, thereby allowing adjustment of parameters for equipment similar to wafer thinning machines.

[0054] Plasma concentration is measured using a temperature sensor, a pressure sensor, or a specially structured Langmuir probe. The distribution of plasma within the chamber is detected by measuring the plasma concentration.

[0055] It should be noted that the wafer can be made of silicon, sapphire, carbon fiber or high-strength metal, with a thickness ranging from 300 micrometers to 1200 micrometers. The main control circuit 2, sensor set 3, wireless signal transmission circuit 5 and battery 6 can be attached to the surface of wafer 1 or integrated into the interior of wafer 1.

[0056] Combination Figures 3-5 As shown, in one embodiment, both the battery 6 and the main control circuit 2 are housed within a high-temperature insulation structure. The sensor assembly 3 is connected to the main control circuit 2 within the high-temperature insulation structure via a wafer surface circuit 10. The wafer surface circuit can be attached to the surface of the wafer 1 using processes such as post-grooving metal sintering, metal screen printing, metal deposition, or post-etching metal deposition. Preferably, the wafer surface circuit 10 is electroplated with silver, exhibiting an adhesion strength ≥5MPa and a resistivity ≤1.5μΩ·cm at high temperatures.

[0057] The high-temperature insulation structure includes a loading box 11, which is suspended on the wafer 1 by a metal sheet 12 and a support foot 13. A heat insulation layer 14 and a phase change layer 15 are provided on the side of the loading box 11 closest to the wafer. A ceramic gasket 16 is provided inside the loading cavity of the loading box 11, and the battery 6 and / or the main control circuit 2 are mounted on the ceramic gasket 16. Thus, through the suspended structure and the heat insulation effects of the ceramic gasket 16, the phase change layer 15, and the heat insulation layer 14, the probability of high-temperature damage to the battery 6 and the main control circuit 2 is effectively reduced.

[0058] Furthermore, by using a metal sheet 12 to fix the support foot 13, and then fixing the metal sheet 12 to the wafer 1, the stability of the loading cassette on the wafer surface is greatly improved. In some embodiments, adhesive is used to fix the metal sheet 12 to the wafer surface; organic adhesives can be used below 250°C, and inorganic adhesives can be used above 250°C.

[0059] The phase change material of the phase change layer 15 is preferably a material with a melting point of 80-120℃, such as bismuth alloy. By utilizing the characteristic that the phase change material absorbs heat during the phase change process, but the temperature remains stable and does not rise, combined with the heat insulation material, the temperature rises step by step and is transferred upward, increasing the lag of temperature transfer.

[0060] The insulation material of the insulation layer 14 can be a ceramic material, such as zirconia ceramic, which can slow down heat transfer.

[0061] This structure significantly reduces the temperature transferred from the wafer surface to the battery 6 and / or the main control circuit 2, thus meeting the requirements for 20 minutes of use at 500°C and 30 minutes of use at 400°C.

[0062] Reference Figure 6As shown, in some embodiments, to avoid back pressure and radio frequency interference from the RF plasma or electrostatic chuck in a vacuum plasma environment from interfering with the normal reading of sensor data, it is preferable that the sensor adopts an anti-interference wafer-integrated packaging method.

[0063] Wafer 1 uses an upper and lower silicon wafer bonding method, with corresponding grooves on the upper and lower silicon wafers. The interlocking grooves together form the sensor mounting cavity 17. An insulating film 18 is placed between the upper and lower silicon wafers to isolate the electric field. The upper and lower silicon wafers are bonded together with adhesive, and the bonding surfaces of the upper and lower silicon wafers are not in the same plane as the sensor circuit board, so that radio frequency interference cannot enter from the side of the wafer and interfere with the normal operation of the sensor circuit.

[0064] The top and bottom silicon wafers are phosphorus-doped, and the phosphorus atoms doped in the silicon wafer can shield electromagnetic fields. Alternatively, ion implantation can be used to inject elements such as phosphorus and boron into the silicon wafer surface to improve the electromagnetic shielding effect.

[0065] The insulating film 18 contains a polyimide radio frequency shielding coating. The polyimide can isolate the electric field and isolate the electrostatic high voltage at the bottom of the wafer during use (the wafer is attracted by an electrostatic chuck, and the voltage range is generally within DC 1-3KV).

[0066] After testing, it was found that the sensor's anti-interference wafer-integrated packaging method, as described above, can still maintain normal operation in RF environments of 2MHz, 13.56MHz, and 60MHz.

[0067] It should also be noted that the technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments have been described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Parts not described in the specific embodiments are all prior art or common knowledge.

Claims

1. A multiphysics in-situ detection system for semiconductor manufacturing processes, characterized in that, The device includes a wafer and a computer terminal; the wafer is equipped with a main control circuit, a sensor set, a wireless signal transmission circuit, a charging and discharging circuit, and a storage circuit. The main control circuit is connected to the sensor set, the wireless signal transmission circuit, the charging and discharging circuit, and the storage circuit. The charging and discharging circuit is used to provide offline power supply. The computer terminal communicates wirelessly with the main control circuit. During operation, the sensor set is used to collect various physical quantities of the semiconductor cavity. The main control circuit stores the collected physical quantities in the storage circuit and transmits them to the computer terminal wirelessly or via wired means. The computer terminal generates a three-dimensional distribution map of the physical quantities and a curve of the physical quantities changing with space and time based on the detection information of each physical quantity using a finite element algorithm, which is used to assist in the debugging of process parameters of semiconductor equipment.

2. The multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 1, characterized in that, The sensor array acquires data in three ways: real-time acquisition, delayed acquisition, and scalar acquisition. Real-time acquired data is transmitted wirelessly back to the computer terminal. Delayed and scalar acquired data are stored in a storage circuit. After the process is completed, the wafer is sent out again, and the data is then read back to the computer terminal. Delayed acquisition refers to acquisition starting after a set time has elapsed. Scalar acquisition refers to acquisition starting after a set parameter has been reached.

3. The multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 1, characterized in that, A wireless charging coil is also mounted on the wafer, and the wireless charging coil is connected to the charging and discharging circuit to realize wireless charging.

4. The multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 3, characterized in that, The wireless charging coil and the charging / discharging circuit are located at the exact center of the wafer.

5. A multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 1, characterized in that, The physical quantities include one or more of the following: temperature, humidity, plasma concentration, air pressure, distance, attitude, particle size, illuminance, and shear force. A continuous temperature-time-space distribution map of the wafer within the cavity is obtained by measuring the temperature. A continuous distribution map of humidity in time and space within the wafer cavity is obtained by measuring humidity. The vacuum level or pressure-time-space continuous distribution map of the wafer in the cavity is obtained by measuring the gas pressure. The distance distribution map between the wafer and the cavity cover is obtained by measuring the distance, which is used to adjust the distance and parallelism between the cover and the wafer. By measuring the attitude, the wafer's velocity, displacement, acceleration, tilt angle, and vibration during the movement process are obtained, thus determining the state of wafer transfer during the wafer transfer process. Through multi-state combined analysis, it can be determined whether there is looseness or other abnormalities in the wafer transfer equipment. On equipment with a rotating structure, the concentricity between the wafer and the rotating structure is obtained by analyzing the attitude data. The environmental particle size of the wafer during its movement is obtained by measuring the particle size. The intensity of different types and wavelengths of light on the wafer surface is obtained by measuring illuminance; The forces applied to the wafer surface, parallel to and perpendicular to the wafer surface, are obtained by measuring the shear force. The distribution of plasma within the chamber is detected by measuring the plasma concentration.

6. The multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 1, characterized in that, After the sensor assembly is mounted on the wafer, it undergoes two calibrations and multiple verifications. The first calibration is to calibrate the acquisition accuracy of the circuit by using a standard load. The second calibration is performed using dedicated calibration equipment for each of the measured quantities; When calibrating with dedicated calibration equipment, multiple calibrations and verifications are performed using cross-validation of data from multiple sources.

7. A multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 1, characterized in that, Both the battery and the main control circuit are mounted in a high-temperature insulation structure. The sensor set is connected to the main control circuit in the high-temperature insulation structure through a wafer surface circuit. The wafer surface circuit is attached to the surface of the wafer using a process of metal sintering after trenching, metal screen printing, metal deposition, or metal deposition after etching.

8. A multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 7, characterized in that, The high-temperature insulation structure includes a loading box, which is suspended on the wafer by a metal sheet and a support foot. The loading box has a heat insulation layer and a phase change layer on the side near the wafer. A ceramic gasket is provided in the loading cavity of the loading box, and the battery and / or the main control circuit is mounted on the ceramic gasket.

9. A multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 8, characterized in that, The phase change material of the phase change layer is a bismuth alloy with a melting point of 80-120℃, and the heat insulation material of the heat insulation layer is a ceramic material.

10. A multiphysics in-situ detection system for semiconductor manufacturing processes according to claim 1, characterized in that, The wafer is bonded together with upper and lower silicon wafers. Corresponding grooves are provided on the upper and lower silicon wafers, and the grooves cooperate to form a sensor mounting cavity. An insulating film is provided between the upper and lower silicon wafers to isolate the electric field. The upper and lower silicon wafers are bonded together with adhesive, and the bonding surfaces of the upper and lower silicon wafers are not in the same plane as the sensor circuit board. The upper and lower silicon wafers are phosphorus-doped silicon wafers, and the insulating film contains polyimide radio frequency shielding coating.

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